DNA agarose electrophoresis gel. The first lane contains a DNA ladder for sizing, and the other four lanes show variously-sized DNA fragments that are present in some but not all of the samples.

The majority of the basic repertoire of the modern proteomics and genomics laboratory consists of techiques of separation and purification. You are almost certain to encounter these techniques in passages, discussion of modes of precipitation, electrophoresis, or chromatography in the background of passages or as their direct subject-matter. Make sure you understand how these techniques work and ensure you understand their rationale in the research context. You need to know how Sanger sequencing works and how PCR works and understand the array of modern variations.

Additionally, you need to get yourself equipped with the basic vocabulary of gene cloning. Passages involving recombinant DNA technology will be trying to push you out of your comfort zone. You can't know everything. This field is too large. But there is the level of fundamentals that will get you situated. A basic understanding of the use of restriction enzymes, screening, and libraries will go a long way. Understand the features and benefits of various cloning vectors. Don't let yourself be intimidated by this material. It's not as difficult as it seems.